I recently purchased a 1993 Jeep Wrangler for off road use. When excellerating hard in a low gear, the engine misses/chugs. Same when decellerating fast in low gear. Problem isn’t as bad when vehicle is warm.

I’m not too familiar with the YJ, but here goes…
The high load misfire could be weak spark or low fuel pressure/volume. For the former, replace distributor cap and rotor, plug wires, and spark plugs. Could also be the coil, but you’ll need to take it to a shop to have it checked. For the latter, check for a clogged fuel filter and check the fuel pump for pressure and volume. I’m not sure about the speedo, probably mechanical for a '93. Also, check the YJ forum on jeepforum.com. Lots of expertise there.